Tapeworms are intestinal parasites similar in shape to tape measures. Their eggs typically enter a human host from animals through food, particularly raw or undercooked meat. Tapeworm eggs can be present in a person’s stool.

A tapeworm cannot live freely on its own. It survives within the gut of animals, including humans.

Humans can contract tapeworms if they have contact with animal feces or contaminated water. When an infection passes from an animal to a human, it is called zoonosis.

Anyone who has a tapeworm will need medical treatment to get rid of it. Treatment is about 95% effective and typically takes a few days.

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Tapeworms that can infect humans include:

  • pork tapeworm (Taenia solium)
  • beef tapeworm (Taenia saginata)
  • fish tapeworm from raw freshwater fish (Diphyllobothrium latum)
  • dwarf tapeworm (Hymenolepis nana)
  • dog tapeworm (Dipylidium caninum)

People who develop tapeworms typically do so after ingesting tapeworm eggs or larvae. Methods of transmission include:

Ingestion of eggs

A human can consume tapeworm eggs through drinking water or consuming food that contains the eggs.

Some people may purposefully ingest pills containing tapeworm eggs in an attempt to lose weight, known as the tapeworm diet. However, this entails risks, including the risk of coinfection with an unexpected parasite that could cause severe harm.

Inadequate hygiene can also lead to tapeworm infections, as eggs enter a person via a fecal-oral route.

Inadequate hygiene may occur when someone is unable to clean themselves regularly, such as washing their hands, particularly after coming into contact with dirt, animals, or feces.

Tapeworm eggs hatch into larvae and make their way into the gut, or outside the gut and infect other parts of the body. This type of infection is most common with tapeworms that come from pigs and is less common if the original host was cattle or fish.

Eating affected meat or fish

If meat or fish have larval cysts and are undercooked or raw, the cysts can travel to the human intestine, where they can mature into adult tapeworms.

The most common sources of fish tapeworm infections include:

  • pike
  • perch
  • whitefish
  • trout
  • salmon
  • burbot

Human-to-human transmission

A 2025 article suggests the dwarf tapeworm can pass from human to human. It is the only tapeworm that can go through its entire life cycle in one single host.

The article suggests dwarf tapeworms affect around 50 to 75 million people worldwide.

Zoonosis

Zoonosis means the transmission of a disease from animals to humans.

Researchers may classify dwarf tapeworm infection as a zoonosis because rodents and certain insects can act as intermediate hosts. People are at risk of infection if they consume an infected insect or feces containing eggs.

After the egg transfers to a human host, the tapeworm transitions from an egg to the adult stage. This type of infection occurs with dwarf tapeworms and is more common in areas where it is more challenging to maintain adequate hygiene.

Reinfection

During treatment, humans can experience reinfection if they have difficulty maintaining hygiene levels.

Tapeworm eggs will be present in human stool. If the individual does not wash their hands after going to the toilet, for example, there is a risk of reinfection.

Exposure to risk factors

According to the Centers for Disease Control and Prevention (CDC), the following factors may increase a person’s risk of tapeworm infection:

  • eating raw or undercooked meat and fish
  • difficulty maintaining adequate hygiene
  • exposure to animal feces

Many people with a tapeworm experience no symptoms and are unaware that they are hosting one.

Symptoms vary depending on the type of tapeworm, and may include the following:

Complications

The risk of complications may depend on the type of tapeworm and whether the person receives treatment. Potential complications include:

  • Cysticercosis: If a human ingests pork tapeworm eggs, the larvae can exit the intestine and travel to tissues and organs elsewhere in the body, causing lesions or cysts.
  • Neurocysticercosis: Neurocysticercosis is a complication of a pork tapeworm infection affecting the brain and nervous system. In severe cases, the infection can be fatal.
  • Echinococcosis, or hydatid disease: The echinococcus tapeworm can cause this. The larvae leave the gut and travel to organs, such as the liver. The infection can cause cysts that put pressure on nearby blood vessels and affect circulation.

Anyone who suspects tapeworm infection can speak with their doctor for help. For example, people may have the symptoms above or notice parts of the adult tapeworm in their stool.

A doctor will typically check a person’s stool by sending samples to a lab. Two to three stool samples may be necessary. The doctor may also examine the area around the person’s anus for signs of eggs or larvae.

Additional diagnostic tests may include:

The following treatments may manage tapeworm infections.

Anthelmintics

Praziquantel (Biltricide) is the first-line choice of medication to treat tapeworms. This is a type of anthelmintic, which is a medication that paralyzes or kills a parasite, expelling it from the body.

Another option is albendazole (Albenza). However, the CDC states that neither praziquantel nor albendazole has Food and Drug Administration (FDA) approval for tapeworm treatment.

Some anthelmintic medications are not effective for cestodes such as tapeworms. For example, healthcare professionals may use ivermectin (Heartgard) for roundworms, not tapeworms.

The doctor will check a person’s stool up to 3 months after administering treatment to ensure it works. Treatment with anthelmintics typically has a favorable outcome and leads to a complete resolution of symptoms.

Cyst treatment

If the infection affects tissues outside the intestine, people may need medication to treat symptoms, such as seizure medication or a course of anti-inflammatory steroids to reduce swelling due to cysts.

If someone has life threatening cysts in vital organs such as the lungs or liver, they may need surgery. A doctor may inject a cyst with medication, such as formalin, to destroy the larvae before removing the cyst.

Research into natural anthelmintics

Researchers are also investigating natural anthelmintics for tapeworm treatment, which may be helpful for parasites that have developed resistance to current medications.

Various plant extracts offer therapeutic potential for parasite treatment. A 2022 review suggests extracts from the following plants may offer anthelmintic activity:

  • walnut
  • papaya
  • asparagus
  • white clover
  • cinnamon

Research into natural anthelmintics is ongoing, and further studies are necessary to understand their effectiveness at treating tapeworms and whether they are a suitable alternative to current medical treatments.

People can speak with a healthcare professional about alternatives to anthelmintic medications. If someone has signs of a tapeworm, they should speak with a doctor before using natural remedies.

The following strategies may help people prevent tapeworms:

  • Wash the hands thoroughly with soap and water after using the bathroom, touching animals and insects, and before eating.
  • Wash fruits and vegetables with clean water before eating them.
  • Correctly dispose of animal and human feces.
  • Thoroughly cook meat and fish.
  • Avoid consuming meat or fish that is raw or may be undercooked.
  • Keep raw and cooked foods separate.
  • Wash the hands after touching raw or undercooked meat or fish.

Tapeworms are intestinal parasites that can live inside another animal or plant. A person can ingest them when consuming raw or undercooked meat and fish. Several types of tapeworms can infect humans.

A doctor may ask for stool samples or blood tests to diagnose tapeworms. Tapeworms can be treated through oral medications and laxatives. If a person follows treatment correctly, medications are highly effective.

Tapeworms may not always cause symptoms. If symptoms occur, they may include gastrointestinal upset. People can speak with a healthcare professional for a diagnosis if they have signs of a tapeworm.